Method allocationSize

src/audio_data.ts:134–185

* Returns the number of bytes needed to hold a copy of the audio data.

(options: AudioDataCopyToOptions)

	 * Returns the number of bytes needed to hold a copy of the audio data.
	 */
	allocationSize(options: AudioDataCopyToOptions) {
		this.ensureNotClosed();

		if (!options || typeof options !== 'object') {
			throw new TypeError('options must be an object.');
		}

		// Spec: Compute Copy Element Count algorithm starts here
		const destFormat = options.format ?? this.format!;

		// 1. Check Plane Index (Interleaved vs Planar checks)
		const isPlanar = formatIsPlanar(destFormat);
		if (!Number.isInteger(options.planeIndex) || options.planeIndex < 0) {
			throw new TypeError('planeIndex must be a non-negative integer.');
		}

		if (isPlanar) {
			if (options.planeIndex >= this.numberOfChannels) {
				throw new RangeError('planeIndex out of range');
			}
		} else {
			if (options.planeIndex !== 0) {
				throw new RangeError('planeIndex out of range');
			}
		}

		// 2. Check Frame Offset
		const frameOffset = options.frameOffset ?? 0;
		if (!Number.isInteger(frameOffset) || frameOffset < 0) {
			throw new TypeError('frameOffset must be a non-negative integer.');
		}
		if (frameOffset >= this.numberOfFrames) {
			throw new RangeError('frameOffset out of range');
		}

		// 3. Check Frame Count
		const copyFrameCount
			= options.frameCount !== undefined ? options.frameCount : (this.numberOfFrames - frameOffset);

		if (options.frameCount !== undefined && (!Number.isInteger(options.frameCount) || options.frameCount < 0)) {
			throw new TypeError('frameCount must be a non-negative integer.');
		}

		if (copyFrameCount > (this.numberOfFrames - frameOffset)) {
			throw new RangeError('frameCount out of range');
		}

		const bytesPerSample = getBytesPerSample(destFormat);
		const elementCount = isPlanar ? copyFrameCount : copyFrameCount * this.numberOfChannels;

		return elementCount * bytesPerSample;
	}

	/**
	 * Copies the audio data to a destination buffer.